Electromagnetic switch



1 646,029 1927' D. L.,LINDQUIST ET AL ELECTROMAGNETIC SWITCH Original Filed Feb. 5, 1925 2 Sheets-Sheet 1 5 R O T N E V m ITTORNEV 1,646,029 Oct. 18, 1927- D. n ulsT ET AL ELECTROMAGNETIC SWITCH Original Filed Feb. 5, 1925 2 Sheets-Sheet 2 ATTORNEY Patented Oct. 18, 1927.

UNITED STATES PATENT OFFICE.

DAVID L. LINDQUIST, OF HARTSDALE, NEW YORK, EDWARD L. DUNN, OF EAST OR- ANGE, NEW JERSEY, AND DAVID C. LARSON, OF YONKERSJNEW YORK, ASSIGNORS TO OTIS ELEVATOR COMPANY, OF'JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

ELECTROMAGNETIC swrrcrr.

Original application filed February 3, 1925, Serial No. 6,561. Divided and this application filed 0etobe 10, 1925. Serial No. 61,741.

This application is a division of appli-' cation Serial No. 6,561, filed February 3, 1925.

The present invention relates to electromagnetic switches.

In the parent application above referred to, a system is described for controlling a single elevator. car or a bank of elevator cars. One feature of the system is to have the starting of an elevator car under the control of an operator in the car,'with the stopping of the car, to pick up prospective passengers, under the control of the passengers themselves, without further act of the operator. Push but-tons are provided at the landings, the stopping operations being effected automatically in response to the pushing of the various buttons by the prospective passengers. Another feature of the system resides in automatically signalling the approach of the car about to stop at a landing in response to the pushing of a button for the landing by a prospective passenger.

In order to operations, use is made of electromagnetical- 1y operated switches, the switches being designated floor stop switches and floor signal switches in the parent application. These switches are arranged to be operated in response to the pushing of the corresponding buttons to set the stop and signal C11 cuits. The push buttons, once operated, may be released, each stop switch being maintained in operated condition until the stopping operation is initiated for a. car approaching the respective landing and each signal switch being maintained in operated condition until the car, after being stopped at the respective lending, is being started again.

More particularly therefore, as regards the floor stop switches, the invention relates to switches which are electromagnetically operated to closed position, which are then maintained in closed position with the closing electromagnet deenergized and which are reset in'response to the occurrence of predetermined conditions, in the control circuits and, as regards the floor signal switches, the invention relates to switches.

of the same type provided 'with addiobtain the above described tional contacts which are moved into engagement during the reset operation and which'are maintained in engagement until aftenthe switch is again operated to closed position. i

One feature of the invention is to provide switches-of the above character which are of simple construction and which arev positive'in action for all operations.

Other features and advantages will become Figure 4 is a front elevation of the same.

Referring to Figures 1 and 2, the details of the preferred form 'of floor stop switch will be described. The switchframe is mounted on a panel 11, being secured thereto as by means of screws 12. The frame supports two cores, 13 for the upperor clos ing coil 14 and 15 for the lower or resetcoil 16. The middle portion 17 of the frame, extending outwardly between coils 14 and "16, is formed with two separated sides so as to insure substantially separate magnetic circuits' for the coils. These sides arejoined at their'outer ends so as to form a mounting on which a plate 18 is secured, as by screws 20. This plate extends over a portion' of the ends of both coils to retain them in position. A pin 21, supported by lugs 22 formed on plate 18, forms a pivotal mounting for the contact armature 23. The contact armature 23 extends upwardly tOTOIIIl an operating arm 24 for the movable contact 25. Contact 25 is slidably mounted in an aperture 26 formed in the erid of arm 24, being insulated therefrom by mearis'of in-- 'sulating bushing 27 and washer 28. The bushing and washer are mounted on the contact stem 30 with the flange 31, formed on bushing 27, abutting agaanst the contact tact. The end of arm 24 is arranged between flange 31 and washer 28, being maintained against washer 28 with the switch in open position by means of a spring 36.

A support 37 for the stationary contact 38 is mounted on panel 11, being secured at the rear thereof as by a nut 39. The contact end of support 37 is threaded to receive the stem 40 of the holder 41 for contact block 42. Thus the position of the stationary contact 38 relative to the position ofthe movable contact may be adjusted, a nut 43 being provided on stem 40 for locking the stationary contact in adjusted osition. i

A pin 44, supported by ad itional. lugs 45 formed on plate 18, forms a pivotal mounting for the latching member 46. This latching, member, preferably of non-magnetic material, comprises a pair of arms 47 and 48, through which'pivot pin 44 extends, and a connecting yoke 50. The latching member is biased by weights 51, formed on arms 47 and 48, to turn counter-clockwise,

as viewed inFigure 2, the movement being limited by the engagement of alug 52, formed on the inner side of arm 47, and one of the mounting lugs 45. A projection 53, extending upwardly from yoke 50, cooperates with a lug 54, depending from the horizontally extendin arm 55 of contact armature 23, to latch t e contacts 25, 38 in closed position.

The armature 56 for the reset magnet is pivotally mounted on pin 44 between the lugs 45. A lug 57 extends upwardly from the pivot point of the reset armature 56 to receive an adjustable abutment screw 58. A biasing weight 60, formed on the lower end of reset armature 56, tends to maintain the armature in unattracted position with screw 58, abutting a ainst the projection 61 formed on the exten ed portion 17 of frame 10. A lug 62, formed on the lower end of arm .47, extends in the path of the weight,

60, to be struck thereby as "the reset ..rmature 56 is moved to its, attracted position. Non-magnetic plates 63, provided on the outer ends of c res 13 and 15, serve as spacing -members to prevent the armatures 23 and-56 from being held inby residual magnetism. The terminals 64, providedon the coils 14 and 16, and the binding nuts 65, provided onthe en of the contact support 37 extending to the rear of the panel, are for connecting the switch in the system.

In operation, with the closing coil 14 energizcd in response to the pushing of its button, contacts 25, 38 will beclosed, Spflng 36 yielding to permit the engagement of contact armature 23 and non-magnetic plate 63. "With contact, armatu e 23 in this attracted position, the latching member 46 is free to move into position with projection 53 beneath the lug 54, such movement being caused by the action of gravity on the weights 51. Upon the release of the push button and the consequent deenergization of coil 14, contact armature 23 is moved outwardly by the action of the spring 36 to cause the engagement of lug 54 and projection 53. As this movement is insufiicient to causethe-engagement of the end of arm 24 and washer 28, the contacts 25, 38 are latched in closed position." By this arrangement, the positive latching of the switch in closed position is insured. The switch is illustrated in these-figures in its-latched positionr Upon the energization of reset coil 16, the

reset armature 56 is moved to attracted position. The-reset armature will gain in speed as it is pulled in so that the 60 will strike the lug 62 a hammerblow. This blow insures the tripping out of the latch; i. e., the. movement of projection 53 from under the lug 54, and therefore the release of the contact armature 23. Armature 23 now falls under the action of gravity into the notch 66 formed in the projection 53, separating contacts 25, 38. The outward movement of the contact armature is limited by the engagement of lug 54 with a stop 67 forming one side of the notch 66.

Referring now to Figures 3 and 4, the preferred form of floor signal switch is identical in construction with the floor stop switch above described except that back contacts are provided. The arms 68 and 70 of the latching member 71 are extended below the reset armature biasing weight 60v where they are joined b a yoke 72. These arms 68 and 70 and yo e 72 are so formed as to permit the engagement of the lug 73 formed 7 on arm 68 by weight 60, in the manner described above. The yoke 72 is formed with a depending lug 74 in which a movable contact'75, identical in construction with movable contact 25 of the floor stop switch, is

slidably mounted. The contact support 7 6,

for the stationary contact 77, is identical in construction with the contact support 37 for the floor stop switch, except that it is shortened. At the rear of the panel 11, the support is provided with the securing nut 39 r and binding nuts 65. The large air gap beweight ill) pletes the circuit for a signal lamp, the filament of a tungsten lamp taking a comparatively large initialcurrent and the circuit for the larn filament being through reset coil 78.

In operation. with the closing coil 88 energized, forward contacts 81, 82 will be closed. back contacts 75, 77 will be separated and rojection 83 on latching member 71 will e moved under lug 54. Upon deenergization of closing coil 80, lug'54 will engage roject on 83 to latch the forward contac..- 81,-82 in closed position, as illus trated in the drawing. Upon energization of reset coil 78, weight 60 will not only trip out the latch for the forward contacts 81, 82 but also will cause the closure of back contacts 75, 77. The lug 54 falling into the notch 84 will form a latch for the back contacts, retaining them in closed position. It is to be noted that, upon the energization of the closing coil 80 again, the latch for back contacts 75, 77 is not released until the latching member 71 is free to move into the position with projection 83 beneath lug 54, and therefore not until the forward contacts 81, 82 areclosed.

In the system above referred to, the closing coils of both a floor stop switch and a floor signal switchfor a landing are energized by the pressing of the same button. The back contacts of the floor signal switch are arranged in-a common circuit for these closing coils so that no circuit is completed asv the result of subsequent pushing of the button. A portion of this connection is 1ndicated in Figure 4 by a conductor con necting coil 80 and contact 77. The stopping operation in response to the pushing of a button is initiated by a floor selector machine as a car arrives at its stopping distance from the landing. As a part of the stopping operation, the circuit for the reset coil of the floor stop switch is energized, the consequent separation of contacts 25, 38 breaking the circuit. The selector machine also completes the signal circuit set by a floor signal switch. The system is arranged, however, so that the reset of the signal switch does not occur until the car is being started away from the floor. This late reset operation serves, among other things, to prevent unwarranted reclosure of the corresponding floor stop switch until the stop is fully completed. Prospective passengers sometimes become impatient and push the button several times before a car arrives. This might occur just as the'car is arriving at the floor and after the floor stop switch has been reset. However, reclosure of the floor stop switch, which would cause a later false stop, is prevented by the fact that the floor signal switch back contacts remain separated, and therefore the circuit for the closing coils broken, until the floor signal switch reset operation.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A switch comprising, mally open contacts,

a pair of nora pair of normally closed contacts, means for closing the first contacts, said means comprising an operating member, and means operable to engage the operating member to retain the first contacts in closed position and to separate the second contacts, the parts being constructed and arranged to prevent the operation of the retaining means until the first contacts are closed.

2. A switch comprising, a pair of normal- 1y open contacts, a pair of normally closed contacts, means for closing the first contacts, said means comprising a lever, means operable to engage thelever to retain the first contacts in closed position and to separate the second contacts, the parts being constructed and arranged to prevent the operation of the retaining means until after the first contacts are closed, and means for causing the disen agement of the second named means and t e lever to separate the first contacts and for causing said second means to close the second contacts.

2-3. A switch comprising, a pair of normally open contacts, a pair of normally closed contacts, means for closing the first contacts, said means comprising an operating member. and means for separating said second contacts, the operating member and second named means being constructedand arranged to retain each pair of contacts in their closed position.

4.1K switch comprising, an electromagnet, an armature arranged to be attracted by the electromagnet, said armature being biased to unattracted position, a contact carried by the armature, a stationary contact arranged to be engaged by the first contact with the armature in attracted position, a latching member adapted to engage the armature to latch the contacts in engagement, the latching member being biased to latched position, a third contact carried by the latching member, and a stationary contact arranged to be engaged b the third contact when the latching member is in unlatched position. the parts being so constructed and arranged that the latching member causes the separation of the third contact and the last named stationary contact only when it moves into latched position.

5. A switch comprising, a movable contact, a stationary contact arranged to be engaged by said movable contact, means for moving said movable contact into engagement with said stationary contact, said means comprising an electromagnet, a latching member for latching said contacts in engagement, a second movable contact, a second stationary contact arranged to be engaged by said second movable contact, and means for releasing said latchin member to permit the disengagement o the first named movable contact from the first named stationary contact, said releasing means com prising a second electromagnet, said latching member upon being released causing the engagement of said second movable contact with said second stationary contact.

6. A switch comprising, a movable contact,'a stationary contact arranged to be engaged by said movable contact, means for moving said movable contact into engagement with said stationary contact, said means comprising an electromagnet, a latching member arranged to latch said contacts in engagement, a second movable contact, a second stationary contact arranged to be engaged by said second movable contact, and means for releasing said latching melnber to permit the disengagement of the first named movable contact from the first named stationary contact, said releasing means com prising a second electromagnet, said latching member being further arranged to cause, upon its being released, the engagement of said second movable contact with said second stationary contact and the latching thereof in engagement.

7. A switch comprising; a pair of con tacts; an electromagnet; an armature for said electromagnet, said armature being biased to unattracted position and being arranged to cause the engagement of said contacts upon being attracte and a latching member for said armature, said latching member being provided with a stop for engaging said armature to determine the unattracted position thereof and being further provided with an additional stop for engaging said armature to maintain said contacts in engagement after the deenergization of said electromagnet.

8. A switch comprising; a pair of contacts; an electromagnet; a pivotally mounted armaturefor said electromagnet, said armature being biased to unattracted position and being arranged to cause the engagement of said contacts upon being attracted by said armature; an arm formed on said armature; a pivotally mounted latching member arranged to form a stop for said arm to latch said contacts in engagement after the deenergization of said electromagnet; and means for causing the latching member to disengage said arm, permitting said armature to cause the separation of said contacts, said latching member being further arranged to form an additional stop for said arm to determine the unattracted position of said armature.

9. A switch comprising; a pair of conby said armature;

tacts; an electromagnet; a pivotally mounted armature for said electromagnet, said arma-. ture being. biased to unattracted position and being arranged to cause the engagement of said contacts upon being attracted by said armature; an arm formed on said armature; a pivotally mounted latchin member arranged to form a stop for sai arm to latch said contacts in engagement after the deenergization of said electromagnet; a second electromagnet; and an additional pivotally mountedrarmature arranged to be attracted by the second electromagnet, said additional armature upon being attracted causing the disengagement of the latching member stop and said arm, permitting the first named armature to cause the separation of said contacts, said latching member being further arranged to form an additional stop for said arm to determine the unattracted position of the first named armature.

10. A switch comprising, a frame member, an electromagnet mounted on the frame member, an armature pivotally secured to the frame member and arran ed to be attracted by the electromagnet, said armature being biased to unattracted position, a contact carried by thearmature, a stationary contact arranged to be engaged by the first named contact with the armature in attracted position, an arm formed on the armature, a latching member pivotally secured to the frame member and arranged to form a stop'for the arm when the electromagnet is deenergized to latch the contacts in engagement, said latching member being biased to latching position, a second electromagnet mounted on the frame member, and a second armature pivotally secured to the frame member and arranged to be attracted by the second electromagnet, said second armature being biased to unattracted position, the latching member being disposed in the path of the second armature ut spaced therefrom so that said second armature upon being attracted will strike the latching member a hammer blow causing the latching member to release the first armature, separating the contacts, the latchin member being further provided with an a ditional stop to determine the unattracted position of the first armature.

In testimony whereof, we have signed our names to this specification.

DAVID L. LINDQUIST. EDWARD L. DUNN. DAVID C. LARSON. 

